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Carrow Midget

• Type: Closed Body Enhanced Mannheim, atypical
• Size: 6 Inches / 16 cm
• Material: Plastic
• Scales:
  • Front: A [ B CI C ] D
  • Back: S L T
• HvH best match 2009

With paper slipcover. The body is folded over and the slide fits within. The S L and T scales are marked on the back of the body. The hairline is calibrated front and back, so you can read S against A and T against D. The slide comes out to reveal inch and centimeter scales, decimal equivalents and some unit conversion settings.

The CI scale is marked "C1".

The address is given as Houston 4, Texas, dating the rule to the last few years before ZIP Codes, say about 1957-1962. The instruction sheet clearly states the rule was made for A. M. Carrow, so I have no idea the actual country of origin. (Can't find out who A. M. Carrow is either...)